Of course Halo 3 Special Edition is the best choice. It's just my own opinion, I think it's released recently and worth to do. I just got it after releasing.
And it has some great reviews
http://kotaku.com/gaming/feature/hal...iew-300345.php
Here is the deal I used, you can try
http://www.dealstudio.com/viewtopic.php?t=31747